Safety-valve



(No Model.)

' 2 Sheets-Sheet l. J. M. COALE.

SAFETY VALVE.

Patented Mar. 30, 1886.

2 Sheets-Sheet 2.

(No Model.)

J. M. GOALE.

- SAFETY VALVE.

No. 338,827. Patented Mar. 30, 1886.

M JJM w MMHM A M m I I w w Inter/7134' NY PETERS. Puma- A wm wumu a UNITED STATES PATENT OFFICE.

JOSEPH M. COALE, OF BALTIMORE, MARYLAND.

SAFETY-VA LVE.

SPECIFICATION forming part of Letters Patent No.338,827, dated March 30, 1886.

Application filed January 2, 1886. Serial No. 187,420.

To aZZ whom it may concern.-

Be it known that I, JosErH M. COALE, of the city of Baltimore, and State of Maryland, have invented certain new and useful Improve ments in Safety-Valves and Mufflers, of which the following is a specification.

My improvements have been devised with reference more particularly to the needs of a safety-valve of the general character of that described and shown in my Letters Patent N 0. 315,732, of April 14, 1885; but the same are applicable also to safety-valves of other kinds.

The objects I have in view in my improvements are to prevent the valve from chattering or fluttering, to provide means by which the valve will be centered and adapted to adjust itself to its seat, and also by which the liability of the valve to stick will be greatly reduced if not indeed entirely obviated, and, finally, to render more efficient the muffier portion of the valve. These improvements will be described in the order above stated, and can best be explained and understood by reference to the accompanying drawings, in which Figure 1 is a vertical central section of a safety-valve and muii'ler embodying the several features of my invention in their pre ferred form. Fig. 2 is a like section of a simple pop safety-valve without the muffler. Fig. 3 is a like section of a safety-valve adapted more particularly for use on marine and stationary boilers. Fig. 4 is a like section of a modification, only so much of the valve being shown as needed to illustrate the modification.

The valve and muffler represented in Fig. 1 in its general organization resembles that illustrated in Fig. 2 of the drawings annexed to my aforesaid Patent No. 315, 732.

A is the mainvalve. B is the outer portion of the same, which may be said to constitute an auxiliary valve.

Z is the valve-case having an internal central guide-tube, Z, for reception of the winged valve-stem b.

D is the adjustable case or sleeve screwing and adjustable upon the exterior of the valvecase Z, and provided with an internal lip, W, to co-operate with the auxiliary valve part B.

(No model.)

G is the spring-case N is the muffler shell or case, made in this instance in one casting with the springcase G and adjustable sleeve D.

M are the passages through which the steam which escapes from between the valve and the lip W is discharged.

S is the perforated dome which surmounts the muffler-case.

P is the tubular stem of cap S, which telescopes into the tubularscrewbolt H, by which the compression of spring F is regulated. Spring F is compressed between the head or flange of the bolt H above and the head or flange of the spindle E below, said spindle below its flange being prolonged and stepped in the valve A, and being formed above its flange with longitudinal wings which enter and fit loosely in the bolt H.

R is the perforated muffler-diaphragm, in this instance made separate from the mufllercase N.

The general organization, arrangement, and mode of operation of the parts thus far described are similar to those of the like-lettered parts in my Letters Patent No. 315,732 above named. No detailed description of the valve, therefore, is required, except in so far as it differs from my patented valve. I now proceed to point out these difierences. The seat for the main valve is shown at a. Between the point a and the point from which the steam escapes from between the lip \V and auxiliary valve B is a sinuous passage, 1), formed by appropriately recessing the face of the valve and the contiguous face of the valve-case X between the points specified. This passage may not improperly be described as having an ogee or approximately ogee form in cross-section. The form shown in the drawings is that which I have found to produce the best results. The top of the passage (formed in the under face of the valve) starting from the seat (4 curves at first upwardly, then downwardly, and finally again extends upwardly and outwardly in a slanting direction. The bottom of the passage (formed in the contiguous face of the part X) has a concave shape, as shown, forming with the top of the passage a chamber of approximately oval form, which at its outer end is continued in the form of an upwardly and outwardly slanting passage, gradually contractoutward movement, and to cause it, or any material portion of it, to whirl backward. It is my present impression, from what practical experience I have had in the manufacture and use of safety-valves, that the chattering or fluttering of the valve is attributable mainly, if not entirely, to the cause just referred to; but whatever may be the true explanation of the phenomenon, I find that by giving the escapepassage substantially the form above indicated the fluttering is effectually suppressed. This feature of my invention is applicable to other forms of safety-valves-as, for instance, to a simple pop valveunprovided with a muffler, as shown in Fig. 2, or to a safety-valve for marine engine or boilers, as illustrated in Fig. 3.

Like letters in all the figures indicate corresponding parts, so that the general construction and arrangement of the valves shown in Figs. 2 and 3 will, in the light of the foregoing description, be understood without further explanation.

With a passage of the form indicated intervening between the points a and W, not only is the valve steadied and prevented from fiuttering, but it is brought under better control, and is rendered more sensitive to any reduction of pressure.

In order to permit the valve to center itself in and adjust itself to its seat, and to prevent liability of its sticking or becoming wedged so that it cannot move, I provide it above with a packing-ring which moves in a suitable guide, and is so formed and arranged that while at all times adapted to move, without sticking, up and down in said guide, according as the valve lifts or closes,it will permit the valve to center and adjust itself to its seat. This packing-ring is located in a head above the top of the valve, the space between which head and valve is in free communication with the discharge or blow-off passage or passages M. The

escaping steam enters this space and its press,

ure is exerted against the head above and the top of the valve below. Iprefer that the area of the valve exposed to the pressure should slightly exceed that of the head, which is similarly exposed, (as indicated in the drawings,) so that there may be a little back-pressure on the valve to assist the closing action of the spring, but not sufficient, however, to impede the free lift of the valve.

The packing-ring, while it is not steam-tight, nevertheless, serves to confine the steam sufficiently for the purpose. Whatever steam may escape or pass beyond the packing is carried off through the outtake H P S.

In Fig. 1 this packing and guide ring is seated in the periphery of the flange or head E of the spindle E, said head fitting loosely within the lower end of the spring-case G, which serves as the guide. In an annular recess on the upper face and at the outer edge of the head E is placed the packing-ringe, which may be a solid ring or a split ring, and can be of metal or any suitable material. The pack "ing-ring projects beyond the periphery of the head E, so as to fit and bear against the interior of the cylindrical case G, and is held in the recess by an annular retaining-disk, f, of the same diameter as the head E, placed over the packing-ring and secured to the said head by any suitable means. The recess is of such size that the packing-ring (which in this instance is supposed to be a solid metal ring) can slide laterally in it to a limited extent. In this way the spindle can have slight lateral movement without thereby binding the packing-ring and causing it to wedge or stickin the case G. As hereinbefore said, the upper end of the spindle loosely fits in the adj ustingbolt H, and its lower end is loosely stepped in the valve, so that the two may have a limited lateral play independently of each other. The construction shown is that which is preferred, but obviously the guide or packing ring may be otherwise arranged, what is essential being that the valve should be free to adj ust itself to and center itself in itsseat without causing the packing-ring to bind or stick in its guide. In Fig. 3 the spring is inclosed in a cylindrical shell, E of which the head' E forms the bottom, and the packingring esurrounds the upper end of the shell and fits within and is guided by the upper cylindrical part of the adjustable case D. In this valve the spindle E extends up above the top of the tubular adjusting-bolt H, and is combined with a lifting-lever, m, pivoted at m to a standard, 7, and straddling the spindle E just beneath its head E Avertically-split two-part case, I, on top of case D, surrounds the standard y and the upper ends of the spindle and the adjusting-bolt, the two parts of said case being conveniently held together on one side by the pin 00, which forms the-pivot of the lever, and on the other side by a pin, w. The handle end of the lifting-lever to extends out through a slot in case I, which slot also furnishes a passage for the escape of steam that may leak past the packing-ring. I prefer to place the adjustable packing or guide ring upon the head E or upon an extension thereof. In some cases, however, the valve itself (as shown for example, in my Patent N 0. 315,732) is formed and arranged to enter and move in the lower end of the case G as a guide; In this event the packing-ring may be arranged in or placed upon the valve itself at the proper point, as indicated in Fig. 4.

With respect to that portion of my improvements relating to the muffler portion of the valve, I remark that I find in practice that the steam can be broken up and divided and the sound reduced materially by means of an annular hood, M, arranged and held in an enlargement of the muffler-case N, in a position to cover the upper end of the passage M. This hood is preferably of conical or frustoconical form in cross-section, open at the bottom and having perforated sides, as shown. The escaping steam passes up through passage M into the hood, striking against the top,and thence being diverted toward and passing out through the perforated sides. This device acts efficiently as amuffler in conjunction with the other parts without inducing injurious back-pressure.

Having now described my improvements and the best way at present known to me of carrying the same into effect, what I claim, and desire to secure by Letters Patent, is

1. The combination,with the main valve A, the seat a therefor, and the auxiliary valve B and its co-operating lip or seat W, of a sinuous steam-passage, b, terminating in an inclined upchute, decreasing in size toward its outer end, said passage intervening between the main valve and its seat on the one hand and the auxiliary valve and its seat or co-operating lip on the other hand, substantially as and for the purposes hereinbefore set forth.

2. The combination of the valve proper,the seat therefor, the escape or blow-off passage M, the guide-cylinder, the guide head or flange arranged above and connected to the valve substantially in the manner described, so that there shall be between the two a space that is in communication with the blow-offM,and the packing or guide ring carried by said head and fitting and movable up and down in said cylinder, substantially as and for the purposes hereinbefore set forth. I

3. The valve proper, the seat therefor, the spindle E, provided with head E and stepped in the valve, the blow-off passage M, communicating with the space between the head E and the valve, the spring-case G, and the packing or guide ring 0, mounted and laterally movable on the head E and fitting and adapted to move up and down in the springcase G, as and for the purposes hereinbefore set forth.

In testimony whereof I have hereunto signed my name, this 24th day of December, A. D. 1885.

JOSEPH M. COALE.

YVitnesses:

LEE PURcnLL, S. W. BRADFORD. 

